Not a bad image given the altitude Mike, but I reckon it might be worth checking the coatings on the mirror. I have noted that in the last 8-9 months or so your images have taken on a slightly blurred look to them. Very similar to what I saw from Dave P before his mirror started bubbling on the surface. I remember you writing at some point that you were concerned about the coatings. Seeing certainly could a factor but, in moderate seeing conditions, some of the larger polar ovals should be visible in your image. This is a little evident also in your Saturn images too, despite its poor illumination this apparition.
Might be worth a check.
